The field of this invention relates to welding automatic welding equipment and more particularly to a welder for welding thick walled titanium tubes that are able to withstand a substantial amount of internal fluid pressure over a long period of time without failure.
The welding of titanium in the past has been difficult. Generally, if the titanium is thin walled, such as an eighth of an inch, conventional welding techniques can be employed. However, when the titanium gets thicker, such as about one-quarter of an inch, it becomes more difficult to utilized the conventional welding methods.
Within certain equipment, such as aircraft, titanium is being used to a greater extent. The desirability of using titanium is its high strength and its low weight. In the new aircraft that are currently on the drawing boards, titanium tubing is to be utilized for the hydraulic lines.
These hydraulic lines are under a high pressure, such as eight thousand pounds per square inch. These hydraulic lines are not constructed of a single section of tubing. Instead, these hydraulic lines are constructed of a plurality of replaceable segments with these segments being connected together by connectors. Each end of each segment terminates in an end fitting. Each end fitting is to be welded to its respective end of the tubing. Because of the exceedingly high pressures involved, and also of the fact that the tubing is constantly under vibration, these welds must be of the highest possible quality. There cannot be a flaw in one weld as the entire hydraulic line will become inoperable.